It rained here in Paso today, so I wasn't outside cleaning the car this afternoon. I went to start it at 1pm, just before work, and it fired up for a couple of cylinders and died(wife had to drive me to work in the Tahoe). Then I coudn't get anything. It turns over great, thanks to the new Optima battery, but no fire! So I'm going to see if I get spark tommoro(as I was at work all afternoon/evening). If I have spark, then it should be fuel related. I'm thinking a 20 year old fuel pump could be a culprit as the filter was just replaced last year. If that's the case I'll probably upgrade to the baffled 1LE tank found in the early 90's F-body or maybe a 4th gen tank. If indeed it is the pump, I may skip the gtg unless I can bum a ride from a local member who plans on returning Sun. night.? Anyways, anyone on hear besides TraviZ replaced a pump or tank? What pump should I go with if I plan on doing the 6.3 383 in the future? I know I'll probably have to get a fuel psi regulator to reduce the psi for the stock injectors and fuel rails. Traviz, any input is always appreciated as you are doing a similar project on your IROC(save the F1A,lol)? Thanks for your help in advance. I'll wait to post this anywhere else until I know if it's fuel or spark.

 

Push the pin in your schrader valve, fuel should shoot to the hood (Not a very reliable test by the way)

I just had my tank down a couple weeks ago to do the pump. For my TBI I threw in a Delco TPI pump. It works great but you might want to go all out with those plans, I think the Walbro 255 lph pump is pretty much the biggest people generally go and will support big numbers. Not sure if you'll have to modify your current regulation/return setup in the meantime though to handle the flow though, just do a search I know that stuff is all over TGO.

Get the rear of the car up as high as you possibly can and drop the rear as low as you possibly can. If you don't mind the slight extra trouble of unbolting the torque arm and brake line (you'll be unbolting everything else anyway, yes even the LCAs) things are much easier if you just take the whole rear out and set it aside. I didn't do this, but I was fighting the rear the whole time.

Hopefully it's not the pump, post up...

 

Thanks, a buddies coming over with an Ohm meter tommoro. I think I used to hear the pump whine when I 1st turned the key fwd just before the it cranked. I know our 99 Tahoe does. Today it didn't though. Can anyone tell me if they can hear there fuel pump with the ignition key rolled fwd just before it cranks? I know I could hear the fuel return after turning it off. Thanks again,

 

You should definitely be able to hear it prime for 2 seconds with key-on. Have somebody do the key-on and stick your ear on the rear hump just to be sure. I think the FP relay is on the firewall by the fan relays, might want to look into that. Could get lucky (only buy these relays from the dealer trust me!!).

When my pump went I could still hear it whine, but it sounded sick and my fuel pressure was only 3 lbs out of the usual 12.

 

dont really matter what pump you get they all seem to be walbros. I put an edelbrock in the Iroc, and had bennie intall one in the formula. not very hard just a pain in the *** to get the tank out. haveing the rear end completly out helps a bunch.

no modifications needed for a 255lph pump.

 

Thanks, I'll get out the Chilton's and look for my relay tommoro as I can't hear the f.p. prime. I thought I remembered that, but wasn't sure. Thanks, Daniel U
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So the larger pump won't ruin my stock injectors/fuel lines-rails? I don't want to sound lame, just don't want to do any more damage id I don't have to, lol.

 

Good luck with your troubleshooting - You've got several days to get it moving!

http://tpiparts.net/inc/sdetail/4369

 

So this would eliminate the fuel tank drop all together being "external". Thanks for the link. Anyone have any pics of where they installed there external pump?

 

Well, the Gm dealership doesn't carry a fuel pump relay switch, but for 16 bucks, Kragen has 1 in stock. For that price I'm going to replace it anyways. If she still doesn't prime, then I'll know it's the pump. If that happens I may replace the tank and pump together, as the stock tank isn't baffled. I maybe hitch hiking to the gtg, lol.

 

Daniel, call me tomorrow. I will be over there to help if you need it. I had to do mine a few months back, and you really need help wrestling that tank out and then back in. It was a pain in the ***. The rest was easy though, I thought.

If you can think of a way to get it to Cuesta on Saturday, we could use the lift from 9 in the morning to 4 or 5 in the afternoon. Would go a lot quicker if it was up in the air.

Actually... A buddy of mine has a shop in Paso and he said that I could use the lift just about any weekend I needed it. I will check on that too if you want to try to get it towed to a lift.

Anyway, let me know. Catch you later.

 

ok kinda had the same problem ur talking about. check your haynes or chilton manual take a wire about 8 foot long more or less and put one end into the bottom left corner of your ecm under your dash board thats the G terminal. with the ignition OFF. touch the other end of your wire to the positive terminal of your battery. you should hear the fuel pump prime for 2 or 3 seconds. if you do not hear it turn on. then its your fuel pump. no need to turn the ignition on whatsoever. it helps if you have two people that way you can touch the positive terminal and have someone else listen for a noise near your gas tank. of course mine didnt make a noise so i dropped the tank and replaced the pump inside the tank. which was a PITA!!! by myself. after doing all that. i noticed the guy before me had the same problem. and he cut out an access hole in the rear of the car under the carpet. then bolted sheet metal to cover it in case that happens again you can easily change the pump with out dropping the tank. needless to say once the pump was replaced my car fired right up.. hope this helps.

 

Well I replaced the relay this morning and still no prime or start. I'm going to re-post this in the fabrication or TPI section as I plan on replacing the tank with a newer baffled "1LE" tank and the 255 walbro pump. If there is someone who see's something else I'm missing let me know. Looks like my IROC won't make the gtg though.

 

cant believe no one has brought this up yet

if it was the fuel pump relay it would be a HARD START because the oil pressure switch acts as a back up circuit for the fuel pump, so if i the main fuel pump relay dies than once the ecm sees 4psi oil pressure it supplies power to the fuel pump.


so most likley just a dead pump,

i would still like to see you come out in the tahoe or somethin

 

If thats so, go unplug your relay and try to start your car.

 

I did my fuel pump in a couple of hours and we did Travis' in a few more with beer time added, NO access door hack job on either of them.

GIT R DUN!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

Im stil mad about my crooked filler tube :ramble:

 

I'm really bummed my IROC won't make it. I had high hopes for making this run. Been looking FWD to meeting up with all of you in your's. I plan on doing the swap next weekend as I want to get the 1LE tank swapped in. I hate fuel starve on a hard corner. So I need to do some research on what models came with the 1LE tank so I can either order it through GM or a company that speacializes in 3rd gens. I know the 91 and 92's had them. Not sure if they were all baffled though. I want to be sure before replacing it. I also need to find out if the Walbro 255 LPH is capable of being submersed in fuel as it is listed as an external pump. BTW, I planned on replacing the relay switch anyways, when I did the pump as the bracket was broken off the firewall. No big deal, just a few bucks. I'll do the fuel filter as well when the tank comes down. Any other component fuel related or needed with this swap/upgrade? Maybe a fuel pressure regulator? I've seen them on a few members rides before, but others have told me I don't need one for the 255? Thanks, Daniel U

 

the pump Del posted is just an external pump, they make intank pumps also.

don't need a regulater to run the a 255lph pump. most people get adjustable regulaters so they can raise the fuel pressure.

 

the 255 is submersable in fuel, Don't where where you read its external. I know for fact that the Granatelli, Edelbrock, BBK, and Holley are all manufactured for them through walbro, Take your pick, whichever is cheapest.
Also, I have contiplated the idea of the jegs universal baffle kit, with the purchase of a new fuel tank and have it all welded in. This is for when I install an external pump on top of using my in tank. Would work for you as well I imagine.

 

I've spent a few hours researching the "1LE" fuel tank here:
https://www.thirdgen.org/forums/sout...fuel-tank.html
In an attempt to upgrade my fuel system(as I have to pull the tank to replace the pump) I need to locate a few parts. The 1LE fuel sender and the double strainer. It seems that all 90-92 tanks came baffled. I'm going to buy the 255 LPH HP intank fuel pump as well. This is getting expensive!
I've got my nieghbor, who work for a local GM dealership, and Dave Staubli from www.thirdgenusa.com looking for me. Anyone see any other parts vendors I missed?